Problem with night mode and IVS

slaver

n3wb
Oct 25, 2025
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Hi.
DH-IPC-HFW3449EP-S-IL-0280B with NVR5216-EI2.
Would you help me with night mode settings?
When I use mode "Auto" (or "B/W") IVS works well. I get intrusion events and records on NVR. But I have really terrible quality of videos because of rain drops even the rain is very light.
With mode "Color" I have much better picture but IVS doesn't work. No events at all.
I tried to play with different camera settings but no success.
It doesn't matter to me to get colored or B/W records. I just need accurate IVS and somehow "rain drops fix".
Thanks.
 

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All of your settings need to be seen - shutter speed, contrast, brightness, etc. impact how well IVS works.

But whenever it rains, it can be problematic with using camera IR. Main way to eliminate it is with external IR and turn off camera AI.
 
My camera settings are by default.
I've tried to disable "AI by Camera" and enable "AI by Recorder" but NVR doesn't recognize event too if night mode is "Color".
 

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I have old Lyvnal IP-camera at the same place and it's IR works much better. Almost no noise from drops.
I'd say it's not even raindrops, but a light drizzle that's not noticeable except when looking at the camera image.
 
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You do not want to use the AI in the NVR unless the camera doesn't have AI as using the NVR AI cuts the capabilities of the NVR by at least half.

In terms of getting the most out of the camera, here is my "standard" post that many use as a start for dialing in day and night that helps get the clean captures and help the camera recognize people and cars.

Start with:

H264
8192 bitrate
CBR
15FPS and iframes if using 3rd party VMS (30 if using NVR is ok)


Every field of view is different, but I have found you need contrast to usually be 6-8 higher than the brightness number at night.

We want the ability to freeze frame capture a clean image from the video at night, and that is only done with a shutter of 1/60 or faster. At night, default/auto may be on 1/12s shutter or worse to make the image bright.

In my opinion, shutter (exposure) and gain are the two most important parameters and then base the others off of it. Shutter is more important than FPS. It is the shutter speed that prevents motion blur, not FPS. 15 FPS is more than enough for surveillance cameras as we are not producing Hollywood movies. Match iframes to FPS. 15FPS is all that is usually needed.

Many people do not realize there is manual shutter that lets you adjust shutter and gain and a shutter priority that only lets you adjust shutter speed but not gain. The higher the gain, the bigger the noise and see-through ghosting start to appear because the noise is amplified. Most people select shutter priority and run a faster shutter than they should because it is likely being done at 100 gain, so it is actually defeating their purpose of a faster shutter.

Go into shutter settings and change to manual shutter and start with custom shutter as ms and change to 0-8.3ms and gain 0-50 (night) and 0-4ms exposure and 0-30 gain (day)for starters. Auto could have a shutter speed of 100ms or more with a gain at 100 and shutter priority could result in gain up at 100 which will contribute to significant ghosting and that blinding white you will get from the infrared or white light.

Now what you will notice immediately at night is that your image gets A LOT darker. That faster the shutter, the more light that is needed. But it is a balance. The nice bright night static image results in Casper blur and ghost during motion LOL. What do we want, a nice static image or a clean image when there is motion introduced to the scene?

In the daytime, if it is still too bright, then drop the 4ms down to 3ms then 2ms, etc. You have to play with it for your field of view.

Then at night, if it is too dark, then start adding ms to the time. Go to 10ms, 12ms, etc. until you find what you feel is acceptable as an image. Then have someone walk around and see if you can get a clean shot. Try not to go above 16.67ms (but certainly not above 30ms) as that tends to be the point where blur starts to occur. Conversely, if it is still bright, then drop down in time to get a faster shutter.

You can also adjust brightness and contrast to improve the image. But try not to go above 70 for anything and try to have contrast be at least 7-10 digits higher than brightness.

You can also add some gain to brighten the image - but the higher the gain, the more ghosting you get. Some cameras can go to 70 or so before it is an issue and some can't go over 50.

But adjusting those two settings will have the biggest impact. The next one is noise reduction. Want to keep that as low as possible. Depending on the amount of light you have, you might be able to get down to 40 or so at night (again camera dependent) and 20-30 during the day, but take it as low as you can before it gets too noisy. Again this one is a balance as well. Too smooth and no noise can result in soft images and contribute to blur.

Do not use backlight features until you have exhausted every other parameter setting. And if you do have to use backlight, take it down as low as possible.

After every setting adjustment, have someone walk around outside and see if you can freeze-frame to get a clean image. If not, keep changing until you do. Clean motion pictures are what we are after, not a clean static image.
 
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Thank you so much for you help! I'm going to try your advises.
I would just like to ask you again about "You do not want to use the AI in the NVR unless the camera doesn't have AI as using the NVR AI cuts the capabilities of the NVR by at least half".
What capabilities do you mean?
I also have a couple of old not-Dahua cameras and I use IVS "AI by Recorder" for them. I must say that it doesn't work very well. I receive events and records on the NVR but in very strange form. The recording is cut into 20-second clips. Only "General" recording works in Schedule but not "Intelligent" etc.
 
Thank you so much for you help! I'm going to try your advises.
I would just like to ask you again about "You do not want to use the AI in the NVR unless the camera doesn't have AI as using the NVR AI cuts the capabilities of the NVR by at least half".
What capabilities do you mean?
I also have a couple of old not-Dahua cameras and I use IVS "AI by Recorder" for them. I must say that it doesn't work very well. I receive events and records on the NVR but in very strange form. The recording is cut into 20-second clips. Only "General" recording works in Schedule but not "Intelligent" etc.
I’d agree that you should try to use AI by camera rather than by recorder. Only one instance where I have found AI by recorder helpful, and that is when using the Color4k-T180 camera. IVS using the camera’s AI has accurate detection only in the center. Detection to the sides is non existent; however, when initiating AI on the recorder, IVS works better for the entire image.
 
Start with:
H264
8192 bitrate
CBR
15FPS and iframes if using 3rd party VMS (30 if using NVR is ok)
I would like ask about Sub Stream settings. Is default OK or need be adjusted? Does Sub Stream play any part in detection? Sorry for these questions. I'm a newbie with Dahua.
 

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